The present invention relates to implements used in tree felling, and, more particularly, to an implement used to saw trees from beneath ground level.
In many parts of the United States, as in many parts of the world, there is a great deal of rain fall. In these areas, the stands of timber are relatively virgin and there is a wide variety and mixture of tree sizes, including some that are quite large. It has been the experience of those clearing such areas for farming, or other uses, that many of the trees are two big to be cut off or pushed down by known means.
Often, bulldozers are used to clear such land. However, it has been found that in clearing land with bulldozers, smaller trees are uprooted and considerable amount of rock, roots, and other debris is created that is difficult to burn or otherwise dispose of. Furthermore, uprooting trees with a bulldozer often produces large holes in the cleared area which, even though refilled, become soft during rainy weather and therefore make it difficult to farm or otherwise utilize the land. It is also a slow and difficult procedure to push trees out by uprooting, and, of course, there is a limit to how big a tree even the largest dozer can fell.
Even if the trees can be uprooted, it has been found that the large balls of rocks and dirt that cling to the roots prevent these uprooted stumps from being easily disposed of. The whole tree mass with roots, rock and humus is often merely pushed aside into a rubble row and then allowed to dry. However, the drying process may require a year or more during which time the rubble presents many problems, not the least of which is the obstruction created which prevents the entire area from being farmed as a single block or unit.
A further problem attendent the uprooting procedure is the destructive nature thereof. Most timber soils have a relatively thin layer of humus which may be completely destroyed by the uprooting procedure. This distruction of the humus layer may cause a high level of errosion, and may also cut down on the possibility of establishing grass or other farming products in the remaining soil. Great amounts of fertilizer must then be used to replace the lost soil and to obtain the required production from the land.
In view of the above-discussed difficulties, a common procedure in farm land clearing is to cut the large trees with a chain saw, or the like, and then simply leave the stump. However, a better procedure is to cut off the stump or the tree beneath ground level. The cut is made deep enough so that a plow, or other such farm implement, can pass over the remaining stump without damage to the implement.
There are known devices which cut off tree stumps beneath ground level. One such device comprises a pair of flat blades which are affixed to a bulldozer and have cutting teeth formed thereon adjacent a wedging member. A gash is made in a tree using the saw teeth on a first pass and on a subsequent pass the wedging member is engaged in that gash to chip off some of the tree while making a new gash. The process is repeated until the tree stump has been removed. While cutting off tree stumps beneath the ground surface is accomplished by this device, the device is quite slow due to the great number of passes required for completing the operation. Furthermore, the wedging member, when engaged in a gash in the tree, makes steering of the bulldozer quite difficult.
The device embodying the present invention saws a tree stump from beneath ground level during both forward and rearward movement of a saw.